Among modern heating systems, one of the main places is occupied by a water or electric underfloor heating for tiles. Which one is better to choose is not an idle question. Comfort in the house and energy saving depend on this. Water heating is prohibited in multi-storey buildings. Therefore, heating the house with underfloor heating is done mainly with the help of electricity. Heating is controlled by a thermostat mounted on the wall.
The advantage of this method is the uniform heating of the room. At the same time, a decrease in the average temperature in the room by 2-3º will not cause discomfort. Energy savings here will be 10-15%. Especially requires a warm floor under the tile or ceramic tile, cold for the feet.
Types of heaters
The heat is generated by the following heating elements embedded in the floor:
- cables
- mats;
- infrared film.
The modern market offers various options. It remains to choose an electric heated floor for the tile. Which is better? Let's try to figure it out.
Cables
Cables are resistive and self-regulating. All of them are mounted in a cement-sand screed with reinforcement, which takes 3-5 cm of additional room height. In addition, tiles are laid on top, taking up to 2 cm more.
Resistive cable
When electric underfloor heating is installed, the prices are lowest for a resistive heating cable, which can be single- and two-core.
When an electric current passes through it, heat is generated. The cable has constant power. It can be stacked arbitrarily in rooms with complex floor shapes.
Self-adjusting cable
This type of cable differs in principle of operation. It consists of two conductors arranged in parallel. A semiconductor polymer is placed between them. Current flows through it in the transverse direction. In different areas, the heat dissipation in the cable may be different, depending on the room temperature. Therefore, overheating in individual places will not occur if there will be furniture or appliances. It is important that too much load does not damage the cable.
Mats
What kind of underfloor heating to install under the tile , the homeowner decides, but heating mats from an ultra-thin cable glued to the grid are best suited.
They are made in the form of rolls of different widths, with a power of
130-150 watts. Mats are easily connected by terminals. The assembly is reliable if the joints are additionally glued with tape or greased with a special sealant. Connections with the cable going to the thermostat protrude a little, but they can be embedded in the recesses of the floor or wall. High strength and resistance of cable insulation do not require mandatory installation in a sand-cement screed. Mats can be placed in a layer of tile adhesive without waterproofing. The thickness of the warm floor will be insignificant.
Film infrared floor
The heater consists of flat carbon conductors laminated in a roll of a special electrical film. This option was originally intended for laying under floor coverings without screed or adhesive. Not every film floor withstands interactions with the alkaline environment of mortars. It can be used under tiles, but additional waterproofing from polyethylene is required.
The choice of power heaters
When it is planned to make an electric heat-insulated floor for a tile, which one is better suited for power depends on the type of room.
Determination of usable area
Under bulky furniture and household appliances, heating is not done due to overload and violation of normal air circulation. It should be borne in mind that it is advisable to heat at least 70% of the floor of the room, when electric heating is the main source of heat. At the same time, its specific power should be 110-220 W / m 2 . If the usable area is less, you will have to abandon the electric floor or change the layout of the room. For a kitchen or living room, the power is approaching the lower limit, and more is needed in the bathroom, on the loggia or on the ground floor premises. The best option is to work the heating system at 70-75%.
How to calculate the heating element when buying
Before you make a warm floor at home, you need to correctly calculate the power, which depends on the type and area of the room. The figure below shows the types of floors through a thermographic device with heating of different capacities (surface temperature 15-25 ° C).
The room requires a specific power of 100-160 W / m 2 . For an auxiliary heat source, it can be selected to a minimum.
For a room of 20 m 2, the usable area will be 20 · 70/100% = 14 m 2 .
Then the required power will be W = 100 · 14 = 1.4 kW.
When the main source, you need to take the maximum: W = 160 · 14 = 2.24 kW.
The cost of the resistive cable is not very high, and it makes sense to take it as the main source of heating, which is not necessary to use at 100%.
If the cable power is 20 W / m, then the length of the main source is
L = 2.24 · 1000/20 = 112 m.
At the ends of the cable, special couplings are installed. Therefore, they are sold in fixed segments. When buying, you can choose a cable of the required power, close to the calculated one.
How to lay a warm floor
When laying an electric heated floor with your own hands, you should know that thermal insulation is needed from below. It is not worth saving on it, since it is a reliable thermal protection at home. In addition, all the heat generated by the warm floor will go up into the room.
The ceiling is cleaned of debris, covered with waterproofing, and insulation is placed on it. A popular material is polypropylene with a layer of foil located on top. A thin mounting grid is placed on the insulation.
If the floor is loaded with heavy objects, it is advisable to use solid waterproof gypsum-fiber or fiberglass sheets as thermal insulation. They are attached to the base with dowels. To prevent contact of the metal cap with the heating elements, the places for self-tapping screws should be carefully selected.
A cement-concrete screed will be poured from above. So that she does not push the insulation, small cutouts are made in it at intervals. Then the screed will be held on the floor, and not on thermal insulation.
The cable laying step is calculated by the formula: h = S · 1000 / L = 14 · 1000/112 = 125 mm.
The laying plan should first be depicted on a sketch with the designation of the installation location of the thermostat. Usually floor heating is done in zones. The advantage of the method is that they can be connected separately.
A warm floor from a heating cable is laid under a concrete screed, the thickness of which is 3-6 cm. On top of it can be any coating that does not have heat-insulating properties. A warm floor is placed so that it never has furniture. Otherwise, these areas will overheat. Above the place where the temperature sensor is located, do not lay mats, as this can disrupt the operation of the entire system.
Rearranging furniture and covering the self-regulating cable with rugs will not impair its performance. It is convenient to use in small areas of heating. In stationary conditions where furniture is not rearranged, it is more economical to use a resistive cable, as it is cheaper.
The underfloor heating is fixed on the floor with a mounting tape, which is fastened through 30-50 cm with dowels.
Connection of a warm floor
Power supply for the warm floor is carried out by a separate group with the use of RCDs. If the house does not have grounding, it needs to be done. The cable braid must be grounded. Wires to the mains and to the heated floor are held in the wall where the gates are made. A corrugated pipe should be placed in them.
The wires are inserted into the installation box and, together with the cable for the underfloor heating, are connected to the thermostat. The marking in it is as follows: L - phase, N - neutral wire, PE - grounding. Thermostat control is done in each room separately. When installing a warm floor in several rooms, it is advisable to use a multi-channel device. Heating can be turned off or kept to a minimum when no one is using the room. In the bathroom and other rooms with high humidity, the temperature controller is not recommended.
Electric underfloor heating: prices and quality
The cheapest are Chinese-made underfloor heating. Russian products have an average price level. Among Korean models, there is a wide range of prices and quality. When buying, you need to pay attention to the characteristics of the products set out not in advertising, but in the documentation.
The best electric underfloor heating is made by American, Norwegian and Danish manufacturers.
Floors of European manufacturers have the following prices (rubles / sq. M):
- cable - 800-1000;
- heating mat - 1500-2600;
- infrared film - 600-800.
When buying, you should evaluate the cost of the entire kit.
Any underfloor heating electric with your own hands can be easily made if the installation and connection instructions are carefully followed.
Conclusion
Of all the known methods of heating, the most convenient is the electric underfloor heating for tiles. Which is better to choose? It all depends on the desire and ability of the homeowner. High thermal conductivity of ceramics, ease of control, hidden placement, cost-effectiveness, the ability to mount an electric floor heating with your own hands and other advantages of this heating method make it more and more popular.